#include <QApplication>
#include <QMainWindow>
#include <QWebEngineView>
#include <QWebEnginePage>
#include <QVBoxLayout>
#include <QPushButton>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QMainWindow w;

    w.setCentralWidget(new QWidget);
    w.centralWidget()->setLayout(new QVBoxLayout);

    auto page1 = new QWebEnginePage;
    page1->setHtml("page #1");
    auto page2 = new QWebEnginePage;
    page2->setHtml("page #2");

    QWebEngineView *webView = new QWebEngineView();

    QPushButton *button1 = new QPushButton("Page 1");
    w.centralWidget()->layout()->addWidget(button1);
    QPushButton *button2 = new QPushButton("Page 2");
    w.centralWidget()->layout()->addWidget(button2);

    w.connect(button1, &QPushButton::clicked, &w, [webView, page1] () {
        webView->setPage(page1);
    });
    w.connect(button2, &QPushButton::clicked, &w, [webView, page2] () {
        webView->setPage(page2);
    });

    w.centralWidget()->layout()->addWidget(webView);
    w.show();

    a.exec();
    delete page1;
    delete page2;
    return 0;
}